Pneumatic tire gauge



May 31, 1938. R. J. PRATT 2,119,237

PNEUMATIC TIRE GAUGE I Filed om. 19, 1936 a s eets-sheet 2 A ttqrney 1933-, I R. J. PRATT 2,119,287

' PNEUMATIC TIRE "GAUGE I Filed Oct. 19, 1936 v 3 Sheets-Shet 3,

. Inventor My m A itornegs new.

Patented May 31 PNEUMATIC TIRE GAUGE Robert James Pratt, CochranaAlberta, Canada Application October 19, 1936, Serial No. 106,467 4 Claims. (CI. 73-31) UNITED STATES PATENT OFFICE My invention relates generally to means for gauging the pressure within automatic tires, and wparticularly to gauge structure to be incorporated in automobile and similar pneumatic tired wheels; whereby the pressure in that particular wheel can be exhibited on the instrument panel of the automobile or. the like, and an important object of the invention is to provide wheel structure of the character indicated which instantly shows whether or not the pressure in the tire of the particular wheel is at the desired' level, while the automobile or other vehicle is traveling over the ground or while the same is standing still.

Another important object of -my invention is view taken through an embodiment of .the invention.

" 1 Figure 2 is a transverse vertical sectional view taken through Figure 1 approximately centrally. Figure 3 is an elevational view of the outboard side of the wheel structure.

Figure 4 is an elevational view of the indicat- 3 ing panel to be mounted on the instrument panel or the like.

Figure 5 is a transverse vertical sectional view taken through Figure 4 approximately centrally.

Figure 6 is an elevational view of one of the 40 two way inflating valves for the tire.

Referring in detail tothe drawings, the nu-f merali generally designates the usual axle hous 7 ing from which extends the axle spindle 6 hav-' .ing the wheel holding nut I and the washer 8 i 45 clamped against the drum portion 9 of the wheel 50 outturned lip l2 projecting over the inboard edge of the brake drum annulus l3 from which projects the spoke or disk portion ll of the wheel which includes an overhanging portion l5 forming the annular, housing I6 in which the 55 'hub cap I1 is conventionally attached.

In accordance with the present invention a tube I8 is fitted around the hearing In and on the exterior of this tube l8 and by means of the bolts l9 and 20, respectively, are supported the L .l-shaped cross-section annuli 2| and 22, re- 5 spectively, and along the bight portion and the inner portion of the legs thereof are confined flexible pneumatic tubes 23 and 24, respectively, the tube 23 having an open stem 25 leading through the shield II and having connection 10 to a pipe 26. The pneumatic tube 24 has an open stem '21 which has connection to a pipe 28.

The radially "outward arm of each U-.shaped annulus-2|, 22 has therein a series of set screws 29, 30 which work in grooves in the radiallyout- 15 ward side of annular blocks 3| and 32 which are slidably mounted within the arms of the respective annuli 2i and 22, whereby the annular blocks 3| and 32 are prevented from moving too far inboardly and outboardly with respect to the shield II and the housing 9. Flanges 33 and 34 on the facing ends of the annular blocks 3i and 32 act as stops for the ends of the arms of the U-shaped annuli 2! and 22 and the radially inward side of these flanges'slide on the exterior of the tube l8.

Set in a annular opening 35 in the annular block 3| is a removable ball bearing race 36 and in a similar but shallower opening 31' in the face of the annular block 32 is'a ball bearing race 38 and these races confine a series of ball bearings 39 by whose presence the relative movement of the annular block 32 relative to the annular block 3! is made'practically frictionless during the rotation of the wheel relative to the axle housing.

Extending from the inboard face of the annular block 32 are annular projections 40 and M which project into accommodating annular grooves 42 and 43 in the face of the annular 5| leading throughthe annular block 3| to the space between the annular ribs 40 and 4| so as to reach the ball bearing structure with the lubricant. I V .The tube 28 leading from the outboard pneumatic tube 24' leads to the end 50' of the T- I 'end of the head is the cap 53 which closes the inflating end 54 0f this valve. The valve 52 is screwed in place on the usual stem of the pneumatic tire 55.

Thetube leads to one of the air bells or pockets 56 which has connection 51 to the corresponding one of the pressure meters 58 each one of which has a face 60 with indicia 60' on' the panel 6i across which is operated the corresponding pointer 62: Each face 50 is provided with a designation 53- indicating to which of the four 'tires of the automobile or other vehicle the indication has reference. A deflation signalling bulb 54 in a socket 65 in the panel 5! is pro.- vided to indicate whenone or more of the tires is deflated. As indicated in Figure 4 a separate face 60 is provided for each one of the tires of the vehicle and a corresponding tube 26'leads to' the tube 23 of the corresponding tire or wheel. Each of these tubes has an inflating valve 26' by means of which the desired air pressure is placed lathe tubes 23.

There is no pneumatic connection between the tubes 23 and 24 in the gauge mechanism. The

' corresponding meter 58 is operated to show either inflation or deflation by the exertion of pressure thereon or by the relaxing. of pressure thereon by the annular block 3i, and pressure for opthe tire 55. Thus if the pressure in the tire 55 should go down below the predetermined desired level, the tube 24 will relax and the tube 23 which was until the condition of under i n flation of the tire compressed, will expand proportionately and the pressure on the corresponding gauge 58 will be correspondingly relaxed so that the pointer will move in the under inflation direction. The opposite action of the device takes place when over-inflation of the tire 55 exists.

Each of the pointers 62 moves relative to an electrical contact which is concentrically mounted on the face 60 of the'corresponding pressure meter, as shown in Figure 4, and in such a position that the pointer 62 will engage the same and close a circuit only in an underinflated condition of the corresponding tire. Suitable arrangements are provided whereby the switches thus constituted are placed in circuit with the battery circuit of the automobile for lighting the deflation signal bulb 64 whenever one or more of the tires becomes deflated, whereby the driver of the automobile is warned of this condition be-- fore starting the automobile and immediately upon closing the ignition switch, which is interposed in the circuit 'for this purpose.

Although I have shown and described herein a preferred embodiment of my invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in the materials, andin the structure and arrangement of the parts, within the spirit of the invention and the scope of thesubjoined claims.

What is claimed is':-

1. Vehicle wheel structure comprising an axle housing including a drum shield stationary with said axle housing, an axle spindle projecting from said axle housing, a wheel on said spindle including a pneumatic tire and a brake drumand revoluble relative to said drum shield, a first guide fastened to said drum shield, a second guide fastened to said brake drum, said guides being annular and having channels facing each other, a first pneumatic tube confined by the channel of said first guide, a second pneumatic tube confined by the channel of said second guide, an individual pressure gauge to which said first penumatic tube is connectibie, said second tube being connected in communication with the pneumatic tire, and annular slides axially slidably confined in the channels of therespective guides and axially slldable relative to each other and to said guides, said annular slides being located at the axially inward sides of and engaging the respective pneumatic tubes, annular'cooperating rib means and rib receiving recess means on the facing sides of said annular slides.

2. Vehicle wheel structure comprising an axle housing including a drum shield stationary with said axle housing, an axle spindle projecting from said axle housing, a wheel on said spindle including a pneumatic tire and a brake drum and revoluble relative to said drum shield, a first guide fastened to said drum shield, a second guide fastened to said brake drum,'said guides being annular and having channels facing each other, a first pneumatic tube 'confined. by the channel of said firstguide, a second pneumatic tube confined by the channel of said second guide, an individual pressure gauge to which said first pneumatic tube is connectible, said second tube being connected in communication with the pneumatictire, and annular slides confined in the channels of the respective guides and axially slldable relative'to each other and to said guides and engaging the axially inward sides of the respective pneumatic tubes, axially and circumferentially extending rib means and recess means on, said slides, said rib means and said recess 'means being mutually engaged for axial and rotary relative movement, and spring means in said recess means urging said slides apart in opposite axial directions.

3. Vehicle wheel structure comprising an axle housing including a drum shield stationary with said axle housing, an axle spindle projecting from said axle housing, a wheel on said spindle including a pneumatictire and a brake drum and revoluble relative to said drum shield, a first guide fastened to said drum shield, a. second guide fastened to said brake drum, said guides being annular and having channels facing each other, a first pneumatic tube confined by the channel of said first guide, a second pneumatic tube confined by the channel of said second guide, an individual pressure gauge to which said. first pneumatic tube is connectible, said second tube being connected in communication with the pneumatic tire, annular slides confined in the channels of the respective guides and axially slldable relative to each other and to said guides and engaging the axially inward sides of the respective pneumatic tubes, the facing sides of said annular slides having mutually engaging rib means and recess means, said rib means comprising at least two concentric annuli projecting axially and said recess means comprising at least two annular grooves individually receiving said a'nnuli.

4. Vehicle wheel structure comprising an axle housing including a drum shield stationary with said axle housing, an axle spindle projecting from said axle housing, a wheel on said spindle includinga pneumatic tire and a brake drum and revoluble relative to said drum shield, a first first pneumatic tube is connectihle. said second tube being connected in communication with the pneumatic tire, annular slides confined in the channels of the respective guides and axially slidable relative to each other and to said guides and engaging the axially inward sides of the respective pneumatic tubes, the facing sides of said annular slides having mutually engaging rib means and recess means, said rib means comprising at least two concentric annuli projecting axially and said recess means comprising at least 5 two annular grooves individually receiving said annull, a lubricant sealing ring in each of said grooves and slidably engaging the corresponding annulus within its groove, and spring means in the groove behind the lubricantsealing ring 10 and holding the same in sealing position. I

ROBERT J. PRATT. 

